Cleaning Javascript before we start

* Autosave is broken, see issue #297
* The category link stuff is gone, and it's a mistake. It will come back soon, see issue #318
* WideArea won't work with anything but a textarea
* Auto adapt is no use with contenteditable

Issue #307.
Uses `contenteditable=true` in a div / h1 instead of a Javascript resized textarea in the article form. If Javascript is disabled, the form uses the `textarea` and `input`

Issue #307.
Use `contenteditable` div and h1 on page form.

Issue #307.
Ensures placeholder are loaded on new contents.

Issue #307
Merge branch 'milestone/publify-8' into bug/use-contenteditable-in-editor/307